Covered tubular member for positioning in well flow pipe



1960 G. J. DUESTERBERG 2,925,097

COVERED TUBULAR MEMBER FOR POSITIONING IN WELL FLOW PIPE Filed Sept. 8, 195a INVENTOR.

ATTORNEYS Ger/70rd 4/. fives fenbery TUBULAR MEMBER FOR POSITION- ING IN WELL FLOW PIPE COVERED The present invention relates to a tubular member adapted to be positioned in the flow string of an oil or gas well.

'1 Quite often in the drilling of an oil or gas well, more than one producing strata or formation is uncovered. In order to flow the well fluids to the earths surface, it-is desirable to provide a conduit for communicating separately with each producing formation. It is also desirable to separate, or close off, communication between the various producing formations from each other in the well bore. A great deal of difliculty has been encountered with the fiow pipe which extends through one producing formation on down to a lower producing formation, in

that'aswell fluids are discharged from the formation and intolwell pipe, they tend to cut out the pipe and thereby necessitate repair or replacementof the pipe at frequent intervals.

:As a matter of fact, it is not uncommon for wellpipe inz' high pressure areas to be completely eaten out in a matter of days, and, of course, this is extremely trouble-.

some and expensive as a great deal of time and effort is required to replace the pipe, particularly when it is located oneto three miles in the earths surface, and where the oilorgaswell is located in relatively inaccessible areas suchas in water covered areas in the bay or open sea.

.LThepresent invention is directed to a device for overcoming this problem, in that it provides a tubular memberliadapted to be secured in the'well string which inhibits cutting out of the well string and thereby permits thew'ell to flow over an extended :period of time without requiring repairs or. replacement to the well string.

An object of the present invention is to. provide a cover-ing forztabportionof the well pipe to-resist eroding orucuttingtout of. the well pipe by fluid flow therearound. ZStilla furtherobject of the present invention is to provide a covering for a well-pipe, said covering-including a hard, brittle, substantially non-machinable and .molded.

material with a resilient material on each side of said brittle covering to'act as a sho'ck absorbing medium to inhibit damage to the hard,-,brittle.material as the tubular member is positioned in thewell string for use.

tOtheri .objects and. advantages ofthe present invention Willibecome more readilyapparentfrom a consideration ofth'e following descriptionand drawingswherein: Fig. 1 .Tisbroken vertical. sectionalview illustrating the present invention positioned ina wellqstring fomlse; and Fig. 2 is a broken quarter-sectional view illustrating the details of construction of the present invention.

Attention is directed to Fig. 1 of the drawings, wherein a well bore is illustrated at 2, such well bore being provided with a casing 3 which is positioned in the well bore when the drilling operations are completed. The present invention will be described with regard to its use where there are two producing formations in communication with the well bore, but it should be appreciated that it can be equally used in any situation where it is desired to eliminate the cutting action of abrasive fluids, or fluids under high pressure, and regardless of the number of profates Patent ducing formations. 'A producing formation is illustrated at 4 and another formation is illustrated at 5 spaced below the formation 4. In actual practice, the distance be tween the formations 4 and 5 may be a relatively few feet, or it might be a few hundred feet or several thousand feet. t

In order to accommodate flow from the formation 4 and the formation 5, the casing 3 is provided with a plurality of perforations as shown at 6, in order that the fluids may flow from each of the formations 4 and 5 and into the casing 3 to thereafter be flowed to the earths' surface. It is desirable to provide a flow tube for each formation and as shown in Fig. 1 of the drawings,-the'- pipe or tubing. 8 extends downwardly from the earthssurface and terminates adjacent the formation 4 as illustrated at 9. The lower end of the pipe 8 is perforated as shown at 10 so that the Well fluids passing into the casing. 3 from the formation 4 may be conducted inwardlyof the pipe 8 for passage to the earths surface.

)Similarly, a flow pipe 11 is provided which extends:

downwardly in the casing 3 to terminate adjacent the lower producing formation 5 as illustrated at 12, it also being provided with a perforate section 13 at its lower end so that well fluids from the formation 5 mayflow into the tubing '11 for flowing to the earths surface.

t It is desirable to separate the producingformations 4 and:5 from each other and from the top of the well bore.

This maybe accomplished by positioning packers 14 and'-- 1S asillustrated in Fig. 1 of the drawings, in a manner well known in the art. It will be noted that the flow of well fluids from. the producing formation 4 through the perforations 6 in the casing 3 will hit the portion 16 of the tubing 11 which extends between the packers 14 and 15. .Generally, the producing fluids, whether oil or gas,

areabrasive, and. quite often enter intothe casing 3 under substantial pressure.

Heretofore a great deal of difficulty has been encoun tered in that the portion 16 of the tubing 11 is quickly cut out by the. entering well fluids, thereby necessitatingthat the well be worked over for repairer replacement ofthatportion of the tubing 11 which has been eroded l or cut outby the well fluids entering intdthe casing. as described above.

t I haverdiscovered that fluids entering into the ca'sing3. If desired, more than one joint ofupipe can; be provided with the coating so as to providenaasuitable. length of connected joints tospan be-'1 tween -the packers 14 and 15,1as necessary, in order to. provide a:portionof the tubing string 11 which is rung/.1

protected from the. action-of the well. fluids which enter theljperforations 6. 1'

JIhe form of the invention is best it from the cutting action of the well fluids as they enter the perforations 6 and hit against the portion 16 of the tubing string 11. As shown in Fig. 2 of the drawings, the tubular member 20 may be machined on its outer surface 22 so as to provide a recess as illustrated at 23 and a shoulder as shown at 24 thereon. An annular ring member 25 is seated on the shoulder 24 and supports one end of the covering on the tubular member 20. The ring or collar 25 may be secured to the remainder of the covering by any suitable means such as welding as illustrated at 26 for holding the covering and the Patented Feb. 16, 1960 this problem can be overcome by;posit'ioningajoint of pipe in the tubingstring-ll whichis:.provided. with a covering for inhibiting cutting out on: eroding thereof .by the high pressure, or abrasive well? illustrated in Fig. 2 off'the drawings, whereina joint of pipe or tubular: member is illustrated at 20. The tubular member 20. may. be of any. suitable length, and normally pipe joint: lengths are 20,30 or 40 feet, and the covering desig-". nated generally at 21 will be provided substantially. the whole glengthsofrthe joint ofrpipe "soiaswto fully protect are lowered into position in the well bore.

tubular. member 20 together. A collar 25' is positioned onthe other end of the covering 21 as shown in Fig. ,2 of the drawings, and may be provided with circumferentially arranged openings 27 for receiving set screws 28 therein. for locking the collar. 25' in :positionbn the member .20 and against the upper end 290i thecovering as shown in Fig. 2 of .the drawings. Also, aweld 26 maybe arranged on the 'collar 25' and :the covering 21 for locking the covering in position at its. other .end to inhibit movement thereof as the tubing string 11 is lowered into position in the well bore.

The covering 21 includes a coating ofresilient material such as rubber or the like as illustrated at 30. The coats ing30. may be arranged on substantially all of-the outer surface 22 of the tubular member 20 in strip form 3.1 a;shown in Fig. 2 of the drawings. The coating 30 of resilie nt material serves as a shock absorber to protect, the sleeve member .32 from breakage or damage as the ::tubing string 11 is lowered into position in the wellzbore 2. The sleeve 32 covers theentire surface ofthe member 20 between the collars 25, 25' which collars areadjacent each end of the pipeor member 20. The sleeve 32 is formed of hard, brittle material to resist the cutting action of the high pressure well fluid which strikes thereagainst as'it passes through the perforations 6 in the casing 13.

As vshownin Fig.2 of the drawings, the sleeves32 may :be formed by aplurality of tubular members 33 which are in end to end interfitting or overlapping relation asshown in the drawings. More particularly, attention is directed to Fig. .2 of the drawings wherein it will be noted that each .of the tubular members 33 is provided at its ends 35 and 361with recessed portions 35 shown at 37 and 38 respectively, whereby adjacent tubular sections-may be interfitted therewith so that the ends. of adjacent sections overlap each other. In this manner, the surface 20 of the well pipe 'or tubular member 22 is completely shut 01f from anyfluid action, since it would be virtually impossible for any fluid at any appreciable pressure to leak along the line "of contact 39 between the overlapped end portions of the tubular members 33. Generally speaking, the tubular members 33 may be of any suitable lengths, and a suitable-numbermay be provided to cover the surface 22 of thetubular member 20. A second layer of resilientmaterial asshown at 40 is provided on substantially all of the outer surface 41 of the sleeve 32, such resilient material being of rubber or the like and acting as a shock absorber to protect the sleeve 32 from breakage or damage as the tubular member 32and connected pipe sections .Inorder to further protect the sleeve 32, an outer shell ofmetal as illustrated at'42 may be provided which extends from the collar 25 to. collar 25' as shown in the drawings, and is secured to. each collar by means of the welds 26 as previously described herein.

The sleeve 32 may be formed of ceramic or'tungsten carbide, or any other suitable hard brittle materiahwhich will resist theeroding or cutting out action of high pressure well fluids flowing thereagainst. Generally speaking, materials of this type are substantially non-machinabl'efand are usually molded to the desired configuration or-iorm'; it has been discovered that ceramic serves the purpose quite well. I

It been found that when the tubing string is pro- 4 vided with a section or portion 16 having the covering 21 as described herein, the flow action of the well fluids against the pipe will be resisted and the flow string 11 in which the covered pipe or tubular member 20 is positioned will remain in service over a substantial period of time.

Broadly the invention relates to a coated or covered tubular member for resisting the eroding or cutting out action in well bores by fluid action thereagainst.

What is claimed isi' 1. As an article of manufacture a tubular member adapted to be secured in a well pipe string and having threads adjacent each end thereof for securing the member in the well string, a protective coating on said pipe to resist eroding action of.well fluids .under pressure, said coating including, a rubber sleeve adjacent the outer surface of said member, a tubular ceramic lining surrounding and enclosing said rubber sleeve, a rubber coating covering the exterior ofsaid ceramic lining, and a metallic sheath surrounding and enclosing said rubber. coating, and annular abutment means at each end of said protective coating engaged with said tubular-member and said metallicsheath to position said protective coat.- irig on said tubular member.

"2. 'The combination recited in claim 1 wherein ceramic lining .is formed by a plurality of tubular members stacked in end to end interfitting relation.

3. A device for inhibiting cutting. out of well pipe by high pressure fluids including a tubular member having threads for connecting said member with the well ,pipe,.a .wear resistance covering on said member tolinhibit :cutting out thereof by well fluids, said. covering extending substantially the full length of said member,

said icovering includingra hard, brittle, substantially nodmachinable and molded material, and a resilient material on each side of said'brittle covering to act as a shock absorbing medium as said tubular member is positioned for use.

4. A device for inhibiting cutting out of well pipeby high pressure fluids including a tubularmember having threads for connecting said member with the well pipe, a wear resistant covering on said member to inhibit cutting out thereof by well fluids, vsaid coveringextending substantially the full length of said member, said covering including a hard, brittle, substantially nonmachinable .and molded material, a resilient material on each side of said brittle covering to act as a shock absorbing medium as said tubular member is positioned for use, and means for securing said coveringon said tubular member.

5.'The combination recited in claim 4- wherein said securing means'includes annular collar members ateach ,end of said covering and secured on said member'and to'said covering for holding 'said member and covering a V together; H

3 References Cited inthe file of this patent UNITED STATES PA'IEIITS 570,169 r 2,129,680 Durant Sept. 13, 1938 2,464,487 Chappell et a1. Mar, 15, 1949 2,497,978 Carlson Feb. 21, 19 50 2,614,585 Wagstafl? Oct. 21, 

